Chemical composition,antioxidant activity and anti‐lipase activity of Origanum vulgare and Lippia turbinata essential oils

This study reported the chemical composition, phenolic content, antioxidant and anti‐lipase activity of oregano and Lippia essential oils. The major compounds found in oregano essential oil were γ‐terpinene (32.10%), α‐terpinene (15.10%), p‐cymene (8.00%) and thymol (8.00%). In Lippia essential oil, α‐limonene (76.80%) and 1,8‐cineole (4.95%) represented the major compounds. Oregano essential oil had higher phenolic content (12.47 mg gallic acid mL^?1) and DPPH scavenging activity (IC₅₀ 0.357 μg mL^?1) than Lippia essential oil (7.94 mg gallic acid mL^?1 and IC₅₀ 0.400 μg mL^?1, respectively). Both essential oils had similar antioxidant indexes (about 1.2) determined by Rancimat. Moreover, oregano essential oil had also higher anti‐lipase activity (IC₅₀ 5.09 and 7.26 μg mL^?1). Higher phenolic content in the essential oils was related with higher scavenging and anti‐lipase activities. Oregano and Lippia essential oils could be used as natural antioxidants on food products.     

The influence of heat treatment of chickpea seeds on antioxidant and fibroblast growth‐stimulating activity of peptide fractions obtained from proteins digested under simulated gastrointestinal conditions

This study presents the effect of heat treatment of chickpea seeds on biological activity of peptides obtained by in vitro gastrointestinal digestion. The most significant antiradical activity against ABTS^+? expressed as IC₅₀ value was observed for 3.5‐ to 7‐kDa peptide fraction from TC hydrolysate (41.01 μg mL^?1). In turn, peptide fraction of 3.5–7.0 kDa obtained from raw chickpea seeds hydrolysate showed the highest antiradical activity against DPPH^? and Fe²⁺ chelating activity with IC₅₀ value of 20.94 and 52.53 μg mL^?1, respectively. The highest Cu²⁺ chelating activity was observed for peptides obtained from TC hydrolysate (IC₅₀ = 56.60 μg mL^?1). Peptide fraction <3.5 kDa from TC hydrolysate demonstrated the most significant reducing power (0.362 A₇₀₀/μg mL^?1). The peptide fraction of 3.5–7 kDa from TC hydrolysate also showed the highest fibroblast growth‐stimulating activity. These results indicated that the heat treatment process has no significant effect on antiradical activity against DPPH^? and Fe²⁺ chelating ability of peptides.     

Physicochemical characterisation and oxidative stability of refined hoki oil,unrefined hoki oil and unrefined tuna oil

Physicochemical characterisation and oxidative stability of refined hoki oil, unrefined hoki oil and unrefined tuna oil were carried out in the present study. Tuna oil contains a higher percentage of polyunsaturated fatty acids (42.57%) than the hoki oils (28.79–30.13%), which have higher percentages of monounsaturated fatty acids (45.02–47.16%). All oils showed a good ratio of n‐3 to n‐6 fatty acid (7.01–8.10). Cholesterol contents in the unrefined hoki (5149.40 μg g^?1) and tuna (2045.48 μg g^?1) oils were higher than the refined hoki oil (1411.27 μg g^?1). Tuna has a higher concentration of natural α‐tocopherol (752.49 μg g^?1) but lower concentration of vitamin A (110.99 μg g^?1) than unrefined hoki oil (151.44 μg g^?1 and 997.60 μg g^?1, respectively). Higher percentages of unsaponifiable matter were found in the hoki oils (4.90–7.24%) compared with the tuna oil (0.56%). The hoki oils appear more yellow than the tuna oil, which is darker by comparison. Moisture, p‐anisidine value and free fatty acid contents in the hoki oils were lower than the tuna oil. Other indicators of oxidative stability showed that the hoki oils were more stable than the tuna oil.     

Tannin fraction from Ampelopsis grossedentata leaves tea (Tengcha) as an antioxidant and α‐glucosidase inhibitory nutraceutical

Leaf of Ampelopsis grossedentata is a new resource of functional foods with healthful properties. Antioxidant and α‐glucosidase inhibitory activities of water extract (made in the style of drinking), tannin fraction (TF) and dihydromyricetin (DMY) from A. grossedentata leaves were evaluated. The main component of TF was identified as gallotannins. DPPH and ABTS radical scavenging activities and reducing power of TF were superior to those of water extract, however, inferior to those of DMY. In no PBS wash protocol of cellular antioxidant activity assay, DMY and TF exhibited similarly, while in PBS wash protocol, the value of TF was higher than that of DMY. In addition, TF possessed the highest α‐glucosidase inhibitory activities (IC₅₀ = 1.94 μg mL^?1), followed by water extract (IC₅₀ = 23.10 μg mL^?1) and DMY (IC₅₀ = 72.21 μg mL^?1). The strong α‐glucosidase inhibitory activity of TF may attribute to the binding capacity to enzymes, as confirmed by fluorescence analysis.     

Antifungal properties and inhibitory effects upon aflatoxin production by Zingiber officinale essential oil in Aspergillus flavus

In this study, the efficacy of ginger (Zingiber officinale Roscoe) essential oil (GEO) in reducing A. flavus growth and aflatoxin production was investigated. Gas chromatography coupled to mass spectrometry and nuclear magnetic resonance spectroscopy showed that the major components of GEO were α‐zingiberene (23.85%) and geranial (14.16%). Mycelial growth of Aspergillus flavus was reduced significantly at a GEO concentration of 150 μg mL^?1, and complete inhibition of conidial germination was observed at a concentration of 10 μg mL^?1. Statistically significant inhibition of ergosterol biosynthesis was detected at a GEO concentration of 10 μg mL^?1. GEO was capable of fully inhibiting aflatoxin production by A. flavus at a concentration of 15 μg mL^?1. The results suggest that low concentrations of GEO are capable of inhibiting aflatoxin production; such ability could be valuable in the upcoming future for agricultural companies to better control aflatoxigenic fungi in agricultural products.     

Phytosterols in banana (Musa spp.) flower inhibit α‐glucosidase and α‐amylase hydrolysations and glycation reaction

Three phytosterols were isolated from Musa spp. flowers for evaluating their capabilities in inhibiting glucosidase and amylase activities and glycation of protein and sugar. The three phytosterols were identified as β‐sitosterol (PS1), 31‐norcyclolaudenone (PS2) and (24R)‐4α, 14α, 4‐trimethyl‐5α‐cholesta‐8, 25(27)‐dien‐3β‐ol (PS3). IC₅₀ values (the concentration of inhibiting 50% of enzyme activity) of PS1, PS2 and PS3 against α‐glucosidase were 283.67, 11.33 and 43.10 μg mL^?1, respectively. For inhibition of α‐amylase, the IC₅₀ values of PS1, PS2 and PS3 were 52.55, 76.25 and 532.02 μg mL^?1, respectively. PS1 was an uncompetitive inhibitor against α‐amylase with K_m at 5.51 μg mL^?1, while PS2 and PS3 exhibited a mixed‐type inhibition with K_m at 52.36 and 2.49 μg mL^?1, respectively. PS1 and PS2 also significantly inhibited the formation of advanced glycation end products (AGEs) in a BSA–fructose model. The results suggest that banana flower could possess the capability in prevention of the diseases associated with abnormal blood sugar and AGEs levels, such as diabetes.     

Polyphenolic composition,antioxidant and antiproliferative effects of wild and cultivated blackberries (Rubus fruticosus L.) pomace

The content of total polyphenolics, antioxidative capacity and antiproliferative activity were tested in wild and cultivated blackberry pomace. Wild blackberry pomace extract Tw2 showed the highest following contents: total polyphenolics (50.16 mg GAE g⁻¹ dw), flavonoids (7.73 mg Qc g⁻¹ dw), flavonols (6.63 mg Qc g⁻¹ dw) and total monomeric anthocyanins (13.40 mg Cy g⁻¹). Tw2 extract significantly inhibited free radicals: IC₅₀^DPPH = 127.76 μg mL⁻¹, IC₅₀^ABTS = 26.53 μg mL⁻¹ and IC₅₀ ^{˙ OH} = 168.62 μg mL⁻¹, and the growth of breast adenocarcinoma IC₅₀^MCF7 = 306.68 μg mL⁻¹ and cervix epitheloid carcinoma cell lines IC₅₀^HeLa = 315.49 μg mL⁻¹. Wild blackberry varieties had higher extraction yields, higher total polyphenolic contents and possessed stronger biological effects compared to cultivated blackberries (P < 0.05). All blackberry extracts showed high biological potential that could be attributed to high total polyphenols and flavonoids content and could be utilised as value-added functional food.     

Effects of physicochemical factors and in vitro gastrointestinal digestion on antioxidant activity of R‐phycoerythrin from red algae Bangia fusco‐purpurea

R‐phycoerythrin (R‐PE) was purified from the red algae Bangia fusco‐purpurea after 35–50% ammonium sulphate fractionation followed by ion‐exchange column chromatography on DEAE‐Sepharose, resulting in a purity (A₅₆₅/A₂₈₀) ratio of 5.1. The circular dichroism spectroscopy results suggested that the structure of R‐PE is predominately helical. The antioxidant activity of R‐PE was studied and revealed changes in conformation and antioxidant activity at different temperatures and pH values. After in vitro‐simulated gastrointestinal (GI) digestion of R‐PE, the scavenging activity of ABTS radical (EC₅₀, 769.9 μg mL^?1), DPPH radical (EC₅₀, 421.9 μg mL^?1), hydroxyl radical (EC₅₀, 32.4 μg mL^?1) and reducing power (A₇₀₀ = 0.5, 625.8 μg mL^?1) were measured. Gel filtration chromatography analysis showed that the molecular weight distribution of the final GI digest that still contained high antioxidant activity was <3 kDa. Our present results indicate that digestion‐resistant antioxidant peptides of R‐PE may be obtained by in vitro GI proteinases degradation.     

Phytochemicals content,antioxidant and hypoglycaemic activities of commercial nutmeg mace (Myristica fragrans L.) and pimento (Pimenta dioica (L.) Merr.)

Commercially dried powder of nutmeg mace (Myristica fragrans) and pimento (Pimenta dioica) spices was investigated for their high performance liquid chromatography phenolic profile and their antioxidant and hypoglycaemic properties by α‐amylase and α‐glucosidase inhibition tests. Generally, mace showed the most promising activity. An interesting protection of lipid peroxidation with an IC₅₀ value of 7.7 μg mL^?1 was found. A significant result was also obtained in ferric reducing ability power assay if compared to the positive control butylated hydroxytoluene (IC₅₀ value of 68.7 μg mL^?1 vs. 63.2 μg mL^?1, respectively). Mace also exhibited the highest carbohydrate‐hydrolysing enzyme inhibitory activity with IC₅₀ values of 62.1 and 75.7 μg mL^?1 against α‐amylase and α‐glucosidase, respectively. Overall, these results support the use of these spices not only as flavouring agent but also as food preservative and functional ingredients.     

In vitro inhibitory effects of cranberry bean (Phaseolus vulgaris L.) extracts on aldose reductase, α‐glucosidase and α‐amylase

The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA‐05 and its wild‐type variety Hwachia against aldose reductase, α‐glucosidase and α‐amylase were examined. The results indicated that the polyphenolics‐rich extracts obtained using 800 g kg^?1 methanol and 500 g kg^?1 ethanol demonstrated inhibitory activities against aldose reductase (IC₅₀ of 0.36–0.46 mg mL^?1) and α‐glucosidase (IC₅₀ of 1.32–1.94 mg mL^?1). The 500 g kg^?1 ethanol extracts also showed α‐amylase inhibitory activities (IC₅₀ of 70.11–80.22 μg mL^?1). Subsequent extracts, prepared further with NaCl and H₂O from precipitates of 800 g kg^?1 methanol or 500 g kg^?1 ethanol extracts, exhibited potent α‐amylase inhibitory activities (IC₅₀ of 17.68–38.68 μg mL^?1). A combination of 500 g kg^?1 ethanol extraction plus a subsequent H₂O extraction produced highest polyphenolics and α‐amylase inhibitors. The SA‐05 α‐amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA‐05 is an advantageous choice for producing anti‐hyperglycaemic compounds.     

Antioxidative and anti‐inflammatory potential of phenolics from purple basil (Ocimum basilicum L.) leaves induced by jasmonic,arachidonic and β‐aminobutyric acid elicitation

The study presents changes in the phenolic levels, antioxidant and anti‐inflammatory potential of purple basil leaves caused by different chemical elicitors: arachidonic acid (AA), jasmonic acid (JA) and β‐aminobutyric acid (BABA). The application of the all tested elicitors increased the concentration of phenolic compounds, including flavonoids and phenolic acids; especially, in comparison with control (457.62 μg g^?1 FW), the rosmarinic acid level significantly increased after AA and JA treatment ‐ 705.0 and 596.5 μg g^?1 FW, respectively. Phenolics from AA‐elicited plants showed the highest anti‐inflammatory activities designated as lipoxygenase (EC₅₀ = 1.67 mg FW mL^?1) and cyclooxygenase inhibition (EC₅₀ = 0.31 mg FW mL^?1). Elicitors' treatments (especially AA and JA) may be a very useful biochemical tool for improving the production of phenolic compounds in purple basil leaves.     

Bifurcaria bifurcata: a key macro‐alga as a source of bioactive compounds and functional ingredients

The aim of this work was to study the proximate composition and the bioactive profile of Bifurcaria bifurcata. It contains 73.31 ± 0.69% of moisture, 8.57 ± 0.11 g per 100 g dry weight (d.w.) of protein, 5.81 ± 0.14 g per 100 g d.w. of lipid content and 30.15 ± 0.00 g per 100 g d.w. of ash. The polyunsaturated fatty acids were the most abundant fatty acid (FA), accounting for 2426.56 mg per 100 g which represents 41.77% of the total FA. The methanolic fraction showed high quantity of polyphenols (220.01 ± 0.010 phloroglucinol equivalents g^?1 extract), DPPH radical reduction capacity (EC₅₀:58.82 μg mL^?1) and oxygen radical absorbent capacity (3151.35 ± 119.33 μmol Trolox equivalents g^?1 extract). The highest antimicrobial effect was observed against Pseudomonas aeruginosa (11.3 ± 1.5 mm) and Saccharomyces cerevisiae (IC₅₀:17.07 μg mL^?1) induced by methanolic and dichloromethane fractions, respectively. Dichloromethane fraction revealed the highest antitumor activity on Caco‐2 and HepG‐2 cells. Bifurcaria bifurcata can be a promising source of bioactive compounds and functional ingredients.     

Efficacy of Acorus calamus L. essential oil as a safe plant‐based antioxidant,Aflatoxin B1 suppressor and broad spectrum antimicrobial against food‐infesting fungi

The study explores the efficacy of Acorus calamus L. essential oil (EO) as a safe plant‐based broad spectrum antifungal, antiaflatoxin, antioxidant food additive. The oil completely inhibited the growth and toxin production of the toxigenic strain of Aspergillus flavus at 0.4 and 0.25 μL mL^?1, respectively. EO exhibited pronounced antifungal activity against sixteen food‐infesting fungal species at 0.5 μL mL^?1. The EO showed strong antioxidant efficacy (IC₅₀ 1.06 μL mL^?1) and nonphytotoxic nature on germination of chickpea seeds. The EO was found nonmammalian toxic showing high LD₅₀ (4877.4 μL kg^?1) for mice (oral, acute). The chemical profile of EO was determined through GC and GC–MS analysis. The findings strengthen the possibility of A. calamus EO as a plant‐based food additive in view of its favourable safety profile, antioxidant and antiaflatoxigenic efficacy and broad spectrum antimicrobial activity against food‐infesting fungi.     

Process optimisation of microwave‐assisted extraction of peony (Paeonia suffruticosa Andr.) seed oil using hexane–ethanol mixture and its characterisation

Ethanol and hexane mixture agent microwave‐assisted extraction (MAE) method was conducted to extract peony (Paeonia suffruticosa Andr.) seed oil (PSO). The aim of the study was to optimise the extraction for both yield and energy consumption in mixture agent MAE. The highest oil yield (34.49%) and lowest unit energy consumption (14 125.4 J g^?1) were obtained under optimum extraction condition: solid‐liquid ratio 0.37 g mL^?1, extraction time 3.72 min, extraction temperature 80.92 °C, ethanol ratio 20.00%. GC–MS results showed that unsaturated fatty acids (UFAs) accounted for 88.60% of total fatty acids in PSO. Moreover, linolenic acid content of 37.35% was the highest UFA and caused PSO to possess good nutrition. PSO in DPPH radical scavenging experiment showed that IC₅₀ value of 28.80 ± 2.13 mg mL^?1 exhibited strong antioxidant property. All experiments proved that mixed solvent MAE is an efficient and promising method to extract PSO. This method can effectively reduce the energy consumption and extraction time.     

Chemical composition,antioxidant and cytotoxicity activities of the essential oils of Myristica fragrans and Morinda citrifolia

BACKGROUND: In this study the chemical composition, antioxidant activities and cytotoxic effect of the essential oils of Myristica fragrans (nutmeg) and Morinda citrifolia (mengkudu) were determined. RESULTS: Thirty‐eight compounds in nutmeg oil and six compounds in mengkudu oil were identified by gas chromatography–mass spectrometry. The free radical scavenging activity of nutmeg oil was superior of that mengkudu oil. The MTT assay of nutmeg oil on human colorectal carcinoma (HCT‐116) and human breast carcinoma (MCF‐7) cell lines showed IC₅₀ values of 78.61 and 66.45 µg mL^?1, respectively. The mengkudu oil exhibited IC₅₀ values of 91.46 and 78.15 µg mL^?1 for HCT‐116 and MCF‐7, respectively. CONCLUSION: The results showed that nutmeg oil can be developed as potent anti‐cancer and antioxidant drugs. Copyright © 2011 Society of Chemical Industry     

Inhibitory activity towards human α‐amylase in wheat flour and gluten

Wheat α‐amylase inhibitors (AI) have been targeted as potential triggers of noncoeliac gluten or wheat sensitivity (NCGS). The aim of this study was to determine AI activity towards α‐amylase from human source in wheat cultivars. Contrary to barley, buckwheat, or oats, high level of AI activity was found in wheat and, to a lesser extent, rye. AI activity (mean IC₅₀ = 137 μg mL^?1) did not vary with respect to ancient or recently developed wheat cultivars. Vital wheat gluten had very high and heat‐stable AI activity (mean IC₅₀ = 23 μg mL^?1), higher than wheat starch (?10 000 μg mL^?1) or acarbose (40 μg mL^?1), a medication for the management of hyperglycaemia and potentially causing digestive disorders due to the accumulation of undigested carbohydrates in the intestine. Data suggest that eating raw wheat gluten, flour or dough could pose a health risk.     

Contribution of different molecular weight fractions to anticancer effect of sweet potato protein hydrolysates by six proteases on HT‐29 colon cancer cells

The contribution of different molecular weight fractions to anticancer effect of sweet potato protein hydrolysates (SPPH) by six proteases on HT‐29 colon cancer cells was investigated. SPPH prepared by six proteases showed certain antiproliferation effect on HT‐29 cells. Compared with other five proteases, SPPH by Alcalase exhibited the highest antiproliferation effect with the lowest IC₅₀ value of 119.72 μg mL^?1. SPPH by Alcalase was further separated into four fractions (>10, 5–10, 3–5 and <3 kDa), and <3 kDa fractions showed the strongest antiproliferation effect, which was 43.87% at 100 μg mL^?1 (P < 0.05). The <3 kDa fractions could cause G2/M cell cycle arrest with increased p21 expression and induce apoptosis via decreasing Bcl‐2 expression, increasing Bax expression and inducing caspase‐3 activation in HT‐29 cells. In addition, <3 kDa fractions could significantly inhibit cell migration of HT‐29 cells. Thus, SPPH might be potentially used as a natural supplement in functional foods.     

Development of polyclonal antibody-based indirect competitive enzyme-linked immunosorbent assay for sodium saccharin residue in food samples

A sensitive and specific polyclonal antibody (PcAb)-based indirect competitive enzyme-linked immunosorbent assay (icELISA) for sodium saccharin is described. 6-Amino saccharin was coupled to carrier protein for artificial antigen by diazotisation. New Zealand white rabbits were immunised to obtain anti-sodium saccharin PcAb and then icELISA was developed. The assay showed high sensitivity and specificity to sodium saccharin, with the 50% inhibition value (IC₅₀) of 0.243 μg mL⁻¹, workable range (IC₃₀–IC₇₀) of 0.050–12.8 μg mL⁻¹ and limit of detection (LOD, IC₂₀) of 0.021 μg mL⁻¹. The average recoveries of sodium saccharin in spiked food samples were estimated ranging from 70.7% to 98.8%. A statistically significant correlation of results was obtained between this new ELISA and previously established HPLC approaches with the food-relevant sodium saccharin concentration range 0–320 μg mL⁻¹ (R² = 0.9887–0.9975). These results indicated that the established ELISA was a potential and useful analytical tool for rapid determination of sodium saccharin residue in food samples.     

Assessment of chemically characterised Rosmarinus officinalis L. essential oil and its major compounds as plant‐based preservative in food system based on their efficacy against food‐borne moulds and aflatoxin secretion and as antioxidant

The study explores antifungal, anti‐aflatoxigenic and antioxidant efficacy of Rosmarinus officinalis essential oil (ROEO) and its major compounds. In addition, the mode of action of ROEO and its practical efficacy as preservative have been assessed. GC‐MS analysis of ROEO identified 16 compounds; α‐pinene, 1,8‐cineole and camphor being the major compounds. The minimum concentration for inhibition of growth and aflatoxin B₁ secretion against A. flavus (LHP‐6) was found to be 1.5, >5.0, 4.0 and 3.0 μL mL^?1 and 1.25, >5.0, 3.5 and 3.0 μL mL^?1 for ROEO, α‐pinene, 1,8‐cineole and camphor, respectively. The IC₅₀ value through DPPH analysis and percentage inhibition of linoleic acid peroxidation of ROEO were 0.042 μL mL^?1 and 71.05%, respectively. The targeted site of antifungal action of ROEO was confirmed as plasma membrane through ergosterol measurement and TEM analysis. Moreover, ROEO significantly protected Piper nigrum fruits against mould infestation upto 6 months in in vivo trial.     

The prevention of fish spoilage by high antioxidant Australian culinary plants: Shewanella putrefaciens growth inhibition

Shewanella putrefaciens is a marine bacterium and a major microbial cause of spoilage in low temperature stored seafood. A survey of fruits and culinary herbs was undertaken on Australian plants with high antioxidant capacities. Twenty‐eight extracts from thirteen plant species were investigated for the ability to inhibit S. putrefaciens growth. Of these, eight extracts (28.6%) substantially inhibited S. putrefaciens growth. The muntries (Kunzea pomifera), lemon aspen (Acronychia acidula) and desert lime (Citrus glauca) extracts were efficient anti‐S. putrefaciens agents, with MIC values ≤3000 μg mL^?1. Of these, the muntries methanolic extract was the most potent growth inhibitor (MIC = 2240 μg mL^?1). The aqueous desert lime extract was also an effective growth inhibitor (MIC of 3857 μg mL^?1), whilst the methanolic bush tomato (Solanum aviculare), aqueous muntries and Davidson's plum (Davidsonia pruriens) extracts displayed moderate S. putrefaciens growth inhibition. All extracts were nontoxic in the Artemia fransiscana bioassay, with LC50 values (>1000 μg mL^?1). Nontargeted HPLC‐QTOF mass spectroscopy (with screening against three compound databases) putatively identified twenty compounds that were present in both inhibitory muntries extracts. The low toxicity of these extracts and their inhibitory bioactivity against S. putrefaciens indicates their potential as natural fish and seafood preservatives.